ICD-10-CM > S00-T88 > T20-T25 > T24 > T24.7 > T24.72 > T24.729 T24.729 Corrosion of third degree of unspecified knee Non-Billable/Non-Specific Codes T24.729A..., initial encounterT24.729D..., subsequent encounterT24.729S..., sequela